The present invention relates to an electronic musical instrument having a MIDI interface capable of transmitting and receiving various musical data for musical operation. More particularly, the invention relates to an electronic musical instrument which can change a timbre according to external control information.
Japanese Patent Application Laid-open No. 59-197090 discloses an electronic musical instrument capable of converting musical tone control information which is externally provided, into internal musical tone control data effective to control characteristics of a musical tone generated by an internal tone generator. More particularly, the disclosed electronic musical instrument operates when the same admits a designation of a timbre which cannot be created, for replacing the designated timbre by another timbre so as to generate musical tones. However, there are easy timbres which can be readily replaced by another timbre and difficult timbres which are not suitably replaced, among various species of instrument timbres. Nevertheless, the conventional electronic musical instrument automatically replaces an unable timbre by an able timbre without practical consideration.
In order to commonly use musical data among different models of the electronic musical instruments, it is desired to assign a common timbre to the different models by an identical timbre code. However, each model has an individual tone generation mechanism with an individual performance. Therefore, each model may have a unique timbre. Further, with regard to the common timbres, a high performance model may install multiple of variations of one common timbre. In application, a simple model having small number of timbre species is used to reproduce musical data which is originally prepared for a complicated model having great number of timbre species. In such a case, the simple model may not be installed with a corresponding timbre. If a missing timbre is replaced by a substitute timbre selected from variations, there is practically no problems. However, if a unique timbre is replaced, the instrument generates inconsistent musical tones to thereby hinder the reproduction of the musical data. Moreover, even with regard to the variations, a simple replacement regardless of timbre installations of individual models may result in rather uniform change of the timbres.